The present invention relates generally to pilot operated hydraulic devices. More particularly, the invention relates to pilot operated variable displacement hydraulic pumps in which the displacement of the pump can be changed to match the requirements of the system in which the pump is used.
Variable displacement pumps are well known in the art, such as shown in U.S. Pat. Nos. 3,941,513 and 3,774,505, both of which are incorporated herein by reference. These pumps include a flow generating means and an actuator responsive to pump outlet pressure to change the displacement of the flow generating means.